The notes, captured by a photographer as Mr Lindell entered the Oval Office, came after the businessman deleted tweets calling for the president to “impose martial law” in seven battleground states won by president-elect Joe Biden in the November election.
Mr Trump has repeatedly falsely claimed that widespread voter fraud took place in the election in favour of the Democrats, and Mr Lindell has publicly supported him in his efforts to overturn the results.
This week, Mr Trump became the first ever US president to be impeached twice for his role in inciting the Capitol riots. Five people died and many more were injured.
President Trump incited the breach by urging his supporters at a nearby rally to “walk down to the Capitol”, adding: “You have to show strength, and you have to be strong.”
Mr Lindell, 59, has been one of Mr Trump’s most public supporters over the last four years and has often parroted conspiracy theories spread by the president and his followers.
Mr Lindell, who is referred to as the “MyPillow guy,” has been embroiled in controversy over the past year after touting a fake coronavirus cure and working more closely with the president.
But who is Mr Lindell and what is his relationship with Mr Trump?
Who is Mike Lindell?
Mr Lindell was born in Mankato, Minnesota, in 1961 and launched several unsuccessful businesses after dropping out of university, before he came up with the idea for MyPillow in 2004.
His previous businesses included a carpet cleaning company, lunch wagons, and a hog farm, as well as a short stint counting cards in Las Vegas when he was 22.
Mr Lindell struggled with addiction to alcohol, cocaine and crack cocaine during the 1980s and 1990s, and lost his house to foreclosure before he was divorced by his first wife.
He started selling pillows in 2004, but continued struggling with addiction, before achieving sobriety in 2009 after praying: “God, I want to wake up in the morning and never have the desire again.”
Mr Lindell, who is an evangelical Christian, claims that when he woke up the next morning his desire for any form of cocaine “was just gone.”
In 2017 he told CNBC that the idea for MyPillow, a foam pillow that holds its shape, came in a dream in 2004, saying: “I got up in the middle of the night — it was about two in the morning — and I had ‘My Pillow’ written everywhere in the kitchen and all over the house.”
Mr Lindell first started selling the pillows at mall kiosks and state fairs later that year, before the business took off in 2011 following a 30-minute infomercial that cost Mr Lindell around $500,000 (£367,958) to produce.
The company’s popularity rapidly grew in the years following the infomercial, but MyPillow has also faced criticisms and complaints about alleged false claims in its advertising of the health benefits of the pillows.
MyPillow settled a $1million (£737,956) lawsuit brought in by several California counties in 2011, that claimed the company had been falsely advertising its product by saying it could treat symptoms of sleep apnea and cerebral palsy.
Despite the criticisms, MyPillow has grown into a large company, having sold more than 30 million pillows worldwide, giving Mr Lindell a net worth of around $300m (£220m).
Mr Lindell has been married and divorced twice, most recently in 2013, and received an honorary Doctor of Business from Liberty University in 2019. He has four children.
What is Mike Lindell’s relationship with Donald Trump
Mr Lindell met Mr Trump in August 2016, while the former was the Republican presidential candidate, and quickly became a public supporter and major donor to his campaign.
He attended the final presidential debate in October 2016, before speaking at a campaign rally for Mr Trump and watching election night coverage at the official Donald Watch Party on 8 November.
At a rally for Mr Trump following his 2016 presidential election victory, Mr Lindell praised him, saying he will be “the most amazing president this country has ever seen in history”.
After attending Mr Trump’s inauguration as a guest on 20 January 2017, the president gave Mr Lindell an inauguration lapel pin as a personal gift, according to the Minneapolis/St Paul Business Journal.
Mr Lindell was pictured sitting next to Mr Trump at an industry roundtable event at the White House later that year, and has continued to support the president at rallies in the years since.
At the 2019 Conservative Political Action Conference, Mr Lindell called Mr Trump “the greatest president in history” and claimed he was “chosen by God.”
However Mr Lindell and Mr Trump caused controversy in 2020, when the MyPillow CEO promoted a fake coronavirus cure in several meetings and public appearances with the president.
He promoted the plant extract, oleandrin, as a Covid-19 “cure”, adding: “This thing works – it's the miracle of all time,” in an interview with CNN. Mr Trump said he would “look at” the plant extract.
The 59-year-old has a financial stake in Phoenix Biotechnology, the company that produces the plant extract, and sits on its board. His claims that oleandrin is a Covid-19 cure have not been substantiated.
Mr Lindell also appeared at numerous public events with Mr Trump in 2020, and announced at a White House press briefing last March that he was converting MyPillow production to produce up to 50,000 face masks for health workers on the front lines of the pandemic.
Following the announcement, Donald Sherman, deputy director of Citizens for Responsibility and Ethics in Washington, said the practice “confirms cronyism is at the root of practically every decision President Trump makes”.
Mr Lindell served as campaign chair for Trump's reelection campaign in Minnesota. In the wake of Mr Biden’s victory, he called for voters in Georgia, a state won by the president-elect, to be jailed.
In now-deleted Twitter posts from December, Mr Lindell called for Mr Trump to impose “martial law” - before he was pictured with notes at the White House this week suggesting the same idea.
Mr Lindell has repeated conspiracy theories forwarded by Mr Trump and his supporters, most recently falsely claiming that members of Antifa were behind the Capitol riots, “dressed as Trump people”.
Politico reported last March that Mr Trump had urged Mr Lindell to run for Minnesota governor in 2022, with the CEO saying later that year that he is “99% sure” about campaigning for the role.